Going through a VPN doesn't make your activities any safer (except for stopping packet sniffing but you aren't using the VPN for security). The VPN just allows you to connect to the internet on Port 443 so that your "Network Guru" can close off all other ports in his router (for his so called security requirements). By going through a VPN all you are doing is sending traffic over Port 443 which is already open in the router. If you were browsing a dodgy/infected/hacker website directly through the router or via VPN, it wouldn't matter, this website would have the same ability to infect your computer, but that's where the local computer antivirus and firewall comes into play. To be 100% safe you'd have to actually stop using the internet. This guy is way too paranoid for his own good, and it's most likely due to his own lack of experience in networking. Sounds like you might be caught up in some type of cult? Get out while you can! You should put the onus back on him to explain to you HOW the VPN would compromise his network. I bet you he couldn't give you a proper explanation and that is why he doesn't want you to do anything. He is scared of the unknown. It's easier just to say NO.